1. Technical Field
The present invention relates to a circuit for restraining a shoot through current, and more particularly a circuit for controlling a driving sequence according to an input signal.
2. Description of Related Art
The conventional power circuit commonly has two transistor switches connected in series between a power supply and a ground, and the conventional power circuit controls the states of the two transistor switches to adjust the power inputted from the power supply. In general, the one at an upper arm of the two transistor switches (referred as the upper-arm transistor switch hereinafter) is a P-type MOSFET, and the one at a lower arm thereof (referred as the lower-arm transistor switch hereinafter) is an N-type MOSFET. Ideally, an input signal can be used to simultaneously control the states of two transistor switches to be ON or OFF. When the input signal is at a low level, the upper-arm transistor switch is switched on and the lower-arm transistor switch is switched off, such that the power of the power supply is transmitted to a rear stage via the on and off of the upper-arm transistor. When the input signal is at a high level, the upper-arm transistor switch is switched off and the lower-arm transistor switch is switched on, thereby stop transmitting the power of the power supply.
However, since the transistor switch cannot be promptly switched between the on state and the off state when an actual circuit is in operation, a shoot through current may be caused to flow to ground through the two transistor switches during the two transistor switches being switched between the on state and the off state, thus resulting in switching loss. Especially when the shoot through current is too larger or lasts too long, the transistor switch may be at risk of burnout due to overheat. Therefore, it is a major consideration in designing a control circuit regarding how to switch the two transistor switches in the control circuit for decreasing the power consumption caused by the shoot through current and meanwhile avoiding damaging the transistor switch.